Gobham geay



(No Model.)

Wii E5555.

G. GRAY.

NAIL.

Patented'Demfi, 1881.

lia /Eflhl 1. a0? z-am- Gray 5 y Ju s.

UNITE TATES PATENT retort.

GORHAM GRAY, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO M. STURGIS GRAY, OFSAME PLACE.

NAIL.

SPECIFICATION forming part of Letters Patent No. 250,525, dated December6, 1881.

Application filed April 15, 1881.

To all whom it may concern:

Be it known th it i, GouHAM GRAY, ot Boston, illassachusetts, haveinvented a new and useful Improvement in Nails, of which the following,in connection with the accompanying drawings, is a description.

My invention relates to nails, and has for its object to produce a nailwhich, when driven in wood, leather, or other material, has a greater I0holding-power than nails now commonly in use, and at the same time isnot liable to split the wood into which it may be driven.

Spikes or nails have been previously made having concaved sides and asharp point, the

shanks being twisted. In such nails,ho\\'ever, the edges form sharpthreads, and the point, being wedge-like, is very liable to split thewood into which the nail is driven. I have discovered by experimentsthat this can be obviated by my invention, which consists in making thenail, having the ordinary rectangular cross-section and uniformthickness throughout its entire length, with a twisted shank having oneor more complete half turns or twists, so that the point, which isrectangularin shape, is brought into the same position relative to theupper or head portions of the nail that itoocupics in the ordinaryuntwisted nails.

o In the drawings, Figures 1 and 2 show different side elevations of anail embodying my invention; and Fig. 3, a section thereof on line a: m,Fig. 1.

The improvement is shown as applied to an ordinary out nail having ashank, a, of uniform thickness throughout its entire length, as shown inFig. 2, and increasing in width from its point 2 to its head 3, as shownin Fig. 1. The point 2, being at its extreme end of the 0 same thicknessas the entire portion of the shank, as shown in Fig. 2, when placedacross the grain of the wood in the well-known mander, will break outthe fibers or grain of the (No model.)

wood fora width equal to the thickness of the nail, and there will be notendency to push or 5 crowd the said fibers aside to split the wood,

as when a wedge shape or sharpened point is employed.

In order to give greater holding strength and prevent the nail frombeing too easily 5o withdrawn from the wood, the lower portion of itsshank is twisted,as shown at b, so that the edges 4 cross the directionof movement of the nail in withdrawing it and resist the said movement.

In order that the wedging action of the nail due to its tapering shape(shown in Fig. 1) shall always come in the same direction or lengthwiseot' the grain of the wood, a definite number of complete half-turns isgiven to the shank in forming the twist I), so that the unt-wisted pointportion 2 ot' the nail is in the same relative position to the uutwistedportion near the head as in the untwisted nail. As shown in thedrawings, three complete half-turns are made; but it is obvious thatanynumber might be made, the number depending upon the length of the shank.

I claim As an improved article of manufacture, a nail having arectangular cross-section and uniform thickness throughout, providedwith a number of complete half-turns in the lower portion of its shank,whereby the untwisted portions near the point and head of the nailsstand in the same relative position to one another as in the untwistt dnail, substantially as and for the purpose set forth.

In testimony that I claim the foregoing I have hereunto set my hand andseal this 2d day of April, 1881. o

GORHAM GRAY. n s.]

